ASOS co-founder Quentin Griffiths died in Thailand under mysterious circumstances.

Quentin Griffiths, co-founder of online retail giant ASOS, died under mysterious circumstances in Thailand. The 58-year-old millionaire died after falling from a window in his apartment building, the Daily Mail reports.

According to the resource, Griffiths fell from the balcony of his 17th-floor apartment in Pattaya. Emergency services found the businessman's body on the ground.

Police stated that there were no signs of a struggle inside the apartment, but added that foul play remains a possibility pending further forensic examinations. The exact cause of Griffiths' death will be determined only after a full investigation, which could take several months, is completed.

A source close to the family told The Sun: "[What happened] is a real mystery. [Police] have used the phrase 'suspicious circumstances' but we don't know anything yet."

The tragedy comes amid an ongoing conflict between Griffiths and his Thai-born ex-wife, who is accused of stealing $670,000 from the company they ran together.

Last year, the millionaire was detained and questioned after his wife alleged he had falsified documents to sell land and company shares without her knowledge. Griffiths denied the charges and was released after questioning.

Griffiths launched ASOS in 2000 with Nick Robertson and Andrew Regan, remaining at the helm until 2005. The company grew into a $4 billion global retailer, with Kate, Princess of Wales, and Michelle Obama among those wearing its own label.

Griffiths subsequently made a fortune of $20 million from selling the shares, and subsequently made additional profits from them.

After divorcing his first wife, with whom he had three children, Griffiths moved to Thailand (around 2007) and married a Thai woman. They had a son and a daughter. The couple separated several years ago.

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